Here is part two..... Note that in both vid's....I sometimes take off the right had of the bar, letting the motor idle along in either first or second....... Cannot do that with success on the stock 8GS.....">

By way of a brief introduction, I've spent the last year and a half recording data on several BMW ECUs using a Wideband O2 sensor (actually a pair of them on the R1200). At this point my list includes extensive logged data, on the road, on R1150 single spark, R1150 dual spark (2004) Motronic MA 2.4, R1200GSA BMS-K and F800S BMS-K (newest LC-1 installation).

All the above bikes (about 7 total with more coming on line) have implemented the Innovate LC-1 and 4/5 of the 7 have both LC-1 and simultaneous GS-911 logging. So at this point, we have a wealth of logged data on how these ECUs work, what features they have, and what AFRs the stock fueling tables with O2 sensors actually produce on the road.

I've read through this great thread in its entirety and find everyone's enthusiasm infectious. And although I've been involved with a lot of LC-1 installs, I've studied the Power Commander products carefully and plan to take data on the PC III USB with Wideband sensor, which is one of the rare Dynojet Closed Loop products. I'm able to take data on the stock sensors and on other products because I added a second O2 bung to my exhaust for just that purpose.

The LC-1 is a very effective way to richen the mixture of a fuel injected bike with stock exhaust and stock intake (and even minor exhaust/intake mods). The stock O2 sensor locks the fueling table to 14.7:1 with enrichments for warmup, acceleration, and throttle angles greater than 40/50 degrees. These enrichments take stock AFRs under 13:1 in many conditions.

When you install something like an LC-1 (and there are others) rather than being stuck with a fixed reference at 14.7:1 you can program the O2 (Lambda) reference to anything, over a broad range. A good place to start is a shift to 6% rich. You do this by moving from lambda equals 1 to lambda equals 0.94, or said in AFR terms from 14.7 to 13.8.

The beauty of this approach is that you keep the BMSK's functional capability 100% intact—especially its very important Closed Loop Adaptation Value capability. The best part is that the LC-1 works with the ECU to make it do the work of adding fuel, they work together, not fighting each other, as a team.

The appeal of the PC V AT is that if you have modified the engine's geometry, you can use a Dyno or Autotune to change the fuel matrix's balance AND add fuel. Doing this assumes you have the skill to evaluate fueling and spark timing on the Dyno, or that you have the skill to select the correct matrix of AFR targets for Autotune (a much more difficult task than it might seem at first blush). The major downside to this approach is that the Closed Loop Adaptive Value capability of the BMSK is DISABLED.

I don't in any way mean to say that you can't create an excellent running bike with a PC V, you can. But the cost and degree of difficulty is not for the regular rider in mot cases. I also want to disclose that after a year and a half of data taking and helping others to install LC-1s (they work great but you've got to be able to wire things), I'm working with a manufacturer to turn three different AFR boosting products into plug n play kits so that they're much easier to install.

Whichever way you add fuel, adding fuel is THE best way to boost the performance of your bike, especially the smooth delivery of power between idle and 3500-4000 RPM.

That's a long introduction. Now I'd like to slowly reply to some earlier posts where I think I could add some clarity from my experiences. I'll try not to wear your patience thin.

Well i must be honest since you wanted to do the definitive end all test to stop the bullshit and do some hard science i became extremely interested in your results . You wanted to baseline and then tune, hopefully not just for more power. I am very interested in getting the bike to perform better economicly and remove this fucking surging because its a pain in the ass. Power increase to me is not that important, i would rather have a nice smooth bike, it goes as fast as it should already.

I want science, not raving reviews that show's the surge in the rpm band and it gone. I want information about how much the fuel/air mixture changes at what rpm. Adding +6 percent to everything is but a hack solution. A workaround rather than a true fix.
That's why i made my cheeky post and hoped you would fall for it.

There's a great article by GAMI aviation on the root of surging and stumbling in lean-burn engines like our Beemers. To them, lean-burn means anything leaner than Best Power Mixture.

Below best power mixture a cylinders power output is affected by the amount of air and the amount of fuel in the charge. If your cylinders aren't equalled balanced for fuel and air. By adding just 4-8% to base fueling you add enough gasoline to consume all the oxygen in the intake mixture such that small differences I fueling no longer matter. Once you've used up all the O2, a little more or less fuel in one cylinder compared to another no longer matters—there's no O2 to burn the fuel.

So although at first blush adding several percent to fueling sounds brute force, it is actually very effective and the reason why it works is well understood.

BMW shipped the early Oilheads to Europe with this richer fueling.

The reason we didn't get them here is because a) you emit too much unburned hydrocarbon and carbon monoxide and b) because if that it's not allowed under the regs.

Roger, lets assume we have a pcv installed with a fuel map built by autotune to simulate the closed loop area at sea level (closed loop disabled). For (a crude) example, we set AFR to 14.7 for all throttle less than 25% and revs less than 5k. How well will the open loop compensate with altitude via pressure and temperature sensors?
In other words, for a given exhaust and intake setup, what do we miss by not having closed loop functionality?

Roger, I welcome your knowledge, and expertise on the subject. I have read several of your threads, on other parts of the forum, and enjoyed them all. I would like to ask though, that we focus on the PC-5 in this thread, as that was the the original intent. I would not like to see this turned into a LC-1 thread, as a much better idea would be to start a new thread.

Roger, I welcome your knowledge, and expertise on the subject. I have read several of your threads, on other parts of the forum, and enjoyed them all. I would like to ask though, that we focus on the PC-5 in this thread, as that was the the original intent. I would not like to see this turned into a LC-1 thread, as a much better idea would be to start a new thread.

Sounds like a plan. I'll kick off an F800GS LC-1 thread. That said, Roger if you have info regarding O2 sensors and the interaction with Autotune and PC-V, I bet it would be appropriate to include that here.

Roger, I welcome your knowledge, and expertise on the subject. I have read several of your threads, on other parts of the forum, and enjoyed them all. I would like to ask though, that we focus on the PC-5 in this thread, as that was the the original intent. I would not like to see this turned into a LC-1 thread, as a much better idea would be to start a new thread.

That's a good idea. If you don't mind though there are some points on the PC V that I can illuminate that would help you and others considering the PC-V choice.

Sounds like a plan. I'll kick off an F800GS LC-1 thread. That said, Roger if you have info regarding O2 sensors and the interaction with Autotune and PC-V, I bet it would be appropriate to include that here.

ebrabaek, how does that sound?

That sounds fantastic. I hope you dont think I'm an idiot. I welcome all input, and I am certain that Roger can contribute much knowledge, to this thread. I think as a LC-1 thread is started, there will be many cross links..... That way it is kept clean, and on track.

That's a good idea. If you don't mind though there are some points on the PC V that I can illuminate that would help you and others considering the PC-V choice.

I'm going to delete the LC-1 status stuff and start a new thread.
RB

It is all good Roger.... No need to delete anything imho, but if we can go from here to the LC-1 thread, I think that will be a very clean approach. I truely, and I think all fellow adventurer does, value your opinion. So off course please share it, as I have many things to learn regarding the PC-5, with or without the AT. I agree with your assessment of that the bmsk, and the Pc-5 don't necessarily work together, on paper, and there are a few qurks, that I am am trying to improve on. One is on the warm up, the bmsk enriches the mixture, and as long as you are under 2% throttle, then all is fine on paper, but as you go above the 2% mark AT now takes over, and bring the global afr, down to in my case a preset of 13.2. Practically though, it has no practical implications, as I have now logged over 2K miles with it, and have had only great things to report. And in this case, no cold start stumble. The 8GS app, does not specify an coolant input, and I have just not gotten around to sniff it out. When you do start the LC-1 thread, please post a link here, as I am very interested in seeing it developed, and think it would be great for the PU community.....

Roger, lets assume we have a pcv installed with a fuel map built by autotune to simulate the closed loop area at sea level (closed loop disabled). For (a crude) example, we set AFR to 14.7 for all throttle less than 25% and revs less than 5k. How well will the open loop compensate with altitude via pressure and temperature sensors?
In other words, for a given exhaust and intake setup, what do we miss by not having closed loop functionality?

Hi Mousitsas, You've asked a good question. The answer is a bit involved but I'll do my best not to overcomplicate a fairly complicated subject. Please look at this as a how the PC V works, not as a critique. Like most manufacturers, they don't have an incentive to clearly tell you all the trade-offs.

First, the simple answer. With or without Autotune, the BMS-K has a built-in Barometric Pressure sensor, a built in intake manifold Air Temperature sensor, a built in Battery Voltage sensor. You can disconnect the O2 sensor any time, and the BMS-K will run Open Loop, producing a fuel pulse based on RPM and TPS angle, and also compensate for Barometric Pressure, Air Temperature, Battery Voltage, and engine Oil Temperature during Warm-Up. These compensations are pretty accurate but not perfect. What the BMSK doesn't compensate for is Air Flow (dirty filter), air Humidity, Fuel Pressure or Fuel injector flow rate (slight clogging) or Ethanol Content of the fuel. That's the area that the BMS-K's powerful Closed Loop routines and Adaptation Values really shine. With Closed Loop running, it nails the correct fueling both in the Closed Loop areas ... and in all Open Loop areas ... using its Adaptation Values that it calculates during Closed Loop. (Of course what BMW considers correct is partly mandated by the EPA which is why we want to add fuel. !)

Autotune is a very different beast from the BMS-K's Closed Loop and Adaptation Values. And you can only have one of them at a time. If you connect the PC V with Autotune, you lose Closed Loop. Another factor to consider is, what does the BMS-K do when it can't run its Closed Loop program. The answer is it goes into a sort of Limp Home mode that is never seen on a Dyno run but that occurs while you ride. Here is how a well adapted R1150 would look, notice the AFR spread on the little insert chart, how tightly it holds to 13.8:1:

Here is the same bike with the O2 sensor disconnected. Notice how the Motronic compensates buy running high fuel and low fuel (rather than a straight line) and in the inset chart, how much the AFRs have been spread out.

So the PC V and Autotune get a stream like the one above and then add or subtract fuel to that up/down stream. Note though, under WOT like the Dyno run, the BMS-K is not running the Limp Home pattern and that's why Dyno tuners don't notice it.

Looking at the sample chart from Dynojet below, Autotune works by you filling in a table of AFR targets organized by Throttle Position and RPM (starting with the default table they provide). I've noticed their AFR targets are basic to say the least and not what you would want. (Something important to know is that the BMW designed targets also include a corresponding entry in the Spark Advance and Spark Dwell tables. Since you don't adjust Spark Timing with Autotune, you're pretty much guaranteed to be off the mark with Spark Advance--leading to the potential for pinging at worst or less than the best power.)

So you start with the table of AFR targets. Then there are two modes according to the write-up:

"The Auto Tune kit can be configured to run and correct at all times or by using the "map switch port" on the PCV. You can set it up so that you can switch back and forth between the tuning modes and the base map settings. You can also configure the Auto Tune kit to wait until the bike is at a certain operating temperature before beginning to make adjustments."

Autotune then fills in an adjustment factor when/if you ride your motorcycle under the TPS/RPM combination. You can see that to get a complete tune you have to run in every cell. The best way to use Autotune is "not running all the time" since these programs are know to be imperfect. You need to do some smoothing between adjacent cells quite often. But for the sake of your question, if you do run in correct-at-all-times mode. Then it will adjust over a few hundred miles depending on your riding style. That is much slower than the BMS-K's Adaptation Routines which have short term and long term trims which operate in realtime.

Going back to the issue of how to fill in the table below or whether to use their stock table, the basic AFR target table they ship looks to rich at low power settings and not rich enough at high power settings based on what I've seen.

Although not depicted here, we saw as high as 18 a/f ratio off idle.... and perhaps even higher. That is the reason for the kengaroo hopp off idle. Test riding it on a dirt track afterwards...... I was able to put put in idle in first, and when going over the small jumps ( 3-4 feet) I just bleeped the throttle while standing, and the bike smoothly clawed it's way up.... No clutch.... Try that on a stocker.......

As I read through the thread late last night I noticed a couple times that your tuner mentioned very high AFRs to you. 18:1, etc.

Other than Overrun Fuel Cutoff mode, which shuts off the injectors entirely, the leanest a stock bike gets is 15.5-16.0 during deceleration. The 18:1 and other high numbers are an error created by the tuner's setup and should not be a concern (or anything to be believed). Somewhere else in the thread there is a good link to the explanation of where these tuner AFR errors come from. But it's mainly due to the speed that exhaust gas gets flushed through the exhaust and with the location of the tailpipe sniffers which can suffer from reversion, meaning that air momentarily goes backwards, into the exhaust.

It's worth noting that during all acceleration, even the stock bike richens the mixture into the 12.8:1 range.

Excellent background Roger. This helps me piece together a mental model for how all these hacks come together.

Quote:

Originally Posted by roger 04 rt

... With Closed Loop running, it nails the correct fueling both in the Closed Loop areas ... and in all Open Loop areas ... using its Adaptation Values that it calculates during Closed Loop. (Of course what BMW considers correct is partly mandated by the EPA which is why we want to add fuel. !)

This is a very important point to keep in mind and the 'necessity' of all these (BoosterPlug, HTCA & Poolside's mods, PowerCommander, Wideband O2 sensor, et al) 'inventions'. It is unfortunate, but understandable, that BMW and OEM's of other street legal machines do not make this something owners can adjust in a more straight forward manner.

Excellent background Roger. This helps me piece together a mental model for how all these hacks come together.

This is a very important point to keep in mind and the 'necessity' of all these (BoosterPlug, HTCA & Poolside's mods, PowerCommander, Wideband O2 sensor, et al) 'inventions'. It is unfortunate, but understandable, while BMW and OEMs of other street legal machines do not make this something owners can adjust in a more straight forward manner.

In terms of having a model for how things fit, here's the block diagram of the R1150 fueling system that I made. The two differences between it and the BMS-K for the F800GS are: 1) There is no Coding Plug on an F800GS, and 2) There is a knock sensor that creates Adaptive Spark Timing. In terms of the basic processes though, it is very close to what you have:

After I created my first diagram of PC III USB with Wideband controller I published an incorrect diagram of how it worked, below. However, because PC V is not Closed Loop, it is very close to how the BMS-K and PC V work together.

As I read through the thread late last night I noticed a couple times that your tuner mentioned very high AFRs to you. 18:1, etc.

Other than Overrun Fuel Cutoff mode, which shuts off the injectors entirely, the leanest a stock bike gets is 15.5-16.0 during deceleration. The 18:1 and other high numbers are an error created by the tuner's setup and should not be a concern (or anything to be believed). Somewhere else in the thread there is a good link to the explanation of where these tuner AFR errors come from. But it's mainly due to the speed that exhaust gas gets flushed through the exhaust and with the location of the tailpipe sniffers which can suffer from reversion, meaning that air momentarily goes backwards, into the exhaust.

It's worth noting that during all acceleration, even the stock bike richens the mixture into the 12.8:1 range.

I dont believe this to be the case. It was not done while pulling, but " driving around" on the dyno. Popping all over the place. I have all the faith in my tuner, and as he have done this for many years. We had the sniffer 4 feet in the pipe, but also verified this on the PC-5 readout. I do believe it did go that high.